For female cancer survivors, "reproductive health and fertility concerns," particularly unintended pregnancy and contraception, "are of great importance," according to researchers led by Molly Quinn of the University of California-San Francisco's School of Medicine's Department of Obstetrics, Gynecology, and Reproductive Sciences and colleagues.

They note that 80% of women diagnosed with cancer before age 50 will survive for at least five years. Cancer treatments can affect future fertility, menstruation and the health of any pregnancies, according to the researchers.

"Although methods of fertility preservation prior to cancer treatment and post-treatment reproductive outcomes have been described in the literature, little research exists on the risk of unintended pregnancy in this population," the researchers wrote. Therefore, they developed a study to examine women's contraception use post-treatment and the effectiveness of oncologists' counseling.

Methods

Between January and September 2010, the researchers surveyed 1,041 non-gynecological cancer survivors ages 18 through 40 via mail (53%) or the Internet (41%).

The survey, which was part of a larger study at UCSF on fertility and cancer treatment, included 174 multiple-choice questions. The questions asked women about their cancer treatment, current contraceptive use, demographic information, fertility preservation use, past obstetric and gynecologic history, and post-treatment quality of life.

The data were combined with the California Cancer Registry and assigned "a unique, anonymous identifier code." To assess their findings in relation to the general population, the researchers compared their data with the National Center for Health Statistics' 2006-2008 National Survey of Family Growth.

Results

Of the 1,041 women who completed the survey, 918 (88%) reported receiving treatment that could compromise fertility. The researchers excluded women who did not resume or could not recall resuming a menstrual cycle post-treatment, as well as those who had received surgical sterilization either before or after treatment, resulting in a final sample of 476 subjects.

The researchers identified 58 (21%) of these respondents as being at risk of unintended pregnancy, which they defined as having resumed a menstrual cycle after treatment, not having been surgically sterilized, reporting unprotected vaginal intercourse in the last month and not wanting to conceive. By comparison, there was a 7.3% risk of unintended pregnancy among all U.S. women with regular menstrual cycles who reported unprotected sex in the previous three months, according to NCHS data.

The researchers identified several factors that were associated with a higher risk of unintended pregnancy, including "[i]ncreasing age." Factors that were associated with a decreased unintended pregnancy risk were a relationship status of single and a higher level of education.

About two-thirds of the 476 women had received pre-treatment counseling about fertility. Counseling was found to have no significant association with unintended pregnancy risk.

Slightly fewer than half of the 918 women who received treatment that could affect their fertility reported using a method of contraception at the time of survey, with barrier methods -- including male or female condoms, the cervical cap and the diaphragm -- being used most frequently, with 25.5% reporting use.

Hormonal contraceptive methods were used by 24.5% of contraception users overall but just 1% of breast cancer survivors. Twenty-one percent of women reported having undergone tubal ligation, while 17.5% used partner vasectomy, 7% reported intrauterine device use and 4% reported using a method not listed in the survey.

Discussion

"Women who survived cancer treatment are at a three times greater risk of unintended pregnancy compared with the general population ... despite pre-treatment counseling," the researchers wrote.

Noting that pre-treatment counseling did not lower unintended pregnancy risk, the researcher suggested that the "absence of uniform guidelines for content of counseling coupled with a remote association between counseling and risky sexual practices may explain the lack of efficacy."

In conclusion, they wrote, "Practitioners caring for survivors should counsel about contraception post-treatment in order to decrease this unacceptably high risk of unintended pregnancy."